Mechanical power transmission system

ABSTRACT

A HIGHER MECHANICAL FORCE OVER UNIFORM DISTANCE IN RESPONSE TO MECHANICAL PRESSURES OR ELECTRIC PULSES OF VARYING AMPLITUDE OVER VARYING DURATION IS PROVIDED FOR ONE OR A MULTIPLE OF DEVICES TO BE SHIFTED BY A SIMPLE, COMPACT, INEXPENSIVE HIGH GAIN POWER TRANSMISSION SYSTEM. AN ELECTRIC MOTOR DRIVEN POWER ROLL HAS ONE OR MORE FLEXIBLE BANDS ARRANGED LOOSELY ABOUT THE PERIPHERY. ONE END OF EACH BAND IS COUPLED TO AN OPERATING LEVER, PREFERABLY IN THE FORM OF A HANGER COMPACTLY ENCIRCLING THE POWER ROLL AND THE BAND ON ONE SIDE. THE HANGER IS PIVOTED ON ONE SIDE OF THE ROLL AND CONNECTED TO ONE END OF THE BAND ON THE OTHER SIDE OF THE ROLL. THE DEVICE TO BE SHIFTED IS ATTACHED TO AN EXTENSION OF THE HANGER NEAR THE PIVOT. THE BAND IS CONNECTED TO THE LEVER ON THE OTHER SIDE OF THE ROLL BEYOND WHICH EXTENDS A DISENGAGING PORTION OF THE LEVER. A PRESSURE ROLLER IS ARRANGED ON AN ARM TO PRESS THE BAND INTO ENGAGEMENT WITH THE PERIPHERAL SURFACE OF THE ROLL. AN ARMATURE IS ARRANGED FOR MOVEMENT IN RESPONSE TO MANUAL PRESSURE ON A KEY OR ELECTRIC ENERGIZATION OF A MAGNET, OR THE LIKE. THE MOVEMENT OF THE ARMATURE IS EXERTED THROUGH A MECHANICAL LATCH TO CAUSE THE ARM CARRYING THE PRESSURE ROLLER TO PRESS THE BAND INTO FRICTIONAL CONTACT WITH THE MOVING POWER ROLL. THE BAND THEN PULLS THE LEVER IN A DIRECTION FOR SHIFTING THE DEVICE AS DESIRED AND OPENING THE MECHANICAL LATCH THROUGH ACTION OF THE DISENGAGING EXTENSION OF THE LEVER. THUS UNIFORM TRAVEL OF THE DEVICE TO BE SHIFTED OBTAINS FROM APPLIED FORCE WHICH IS NOT NECESSARILY UNIFORM AS TO TIME OR AMPLITUDE OR DISTANCE TRAVELED.

arch 23, 1971 R. B. JOHNSON ETAL. 3,572,142

MECHANICAL POWER TRANSMISSION SYSTEM Filed June 2, 1969 ZNVENTORSREYNOLD B.JOHNSON RALPH E. MARRS ATTORNEY United States Patent 3,572,142MECHANICAL POWER TRANSMISSION SYSTEM Reynold Benjamin Johnson, PaloAlto, and Ralph Eugene Marrs, Campbell, Calif., assignors toInternational Business Machines Corporation, Armonk, NY.

Filed June 2, 1969, Ser. No. 829,642 Int. Cl. F16h 27/.00

US. Cl. 74-112 4 Claims ABSTRACT OF THE DISCLOSURE A higher mechanicalforce over uniform distance in response to mechanical pressures orelectric pulses of varying amplitude over varying duration is providedfor one or a multiple of devices to be shifted by a simple, compact,inexpensive high gain power transmission system. An electric motordriven power roll has one or more flexible bands arranged loosely aboutthe periphery. One end of each band is coupled to an operating lever,preferably in the form of a hanger compactly encircling the power rolland the band on one side. The hanger is pivoted on one side of the rolland connected to one end of the band on the other side of the roll. Thedevice to be shifted is attached to an extension of the hanger near thepivot. The band is connected to the lever on the other side of the rollbeyond which extends a disengaging portion of the lever. A pressureroller is arranged on an arm to press the band into engagement with theperipheral surface of the roll. An armature is arranged for movement inresponse to manual pressure on a key or electric energization of amagnet, or the like. The movement of the armature is exerted through amechanical latch to cause the arm carrying the pressure roller to pressthe band into frictional contact with the moving power roll. The bandthen pulls the lever in a direction for shifting the device as desiredand opening the mechanical latch through action of the disengagingextension of the lever. Thus uniform travel of the device to be shiftedobtains from applied force which is not necessarily uniform as to timeor amplitude or distance traveled.

This application is related to co-pending US. patent applications Ser.No. 829,653 filed on the 2nd day of June 1969, of Paul Anthony Gilovich,Reynold Benjamin Johnson, Edward Everett Long, David Harwood McMurtry,Ernest George Nassimbene, Thomas Frank ORourke and George Edmund Pricefor Mechanical Type Printing Apparatus, Ser. No. 829,652 filed on thesame day, of Reynold Benjamin Johnson, Edward Everett Long and GeorgeEdmund Price for a Key Responding Selector Mechanism.

The invention relates to an actuator mechanism for accurately shifting amechanical device, and it particularly pertains to such mechanisms formechanical type printing apparatus but it is not limited thereto.

In the contemporary alphanumeric character printing art, attention isbeing directed to simplified, low cost, manually operated type printingapparatus for use in conjunc tion with data processing systems such ascommercial billing systems, and the like, and Computer AssistedInstructional systems. Such apparatus is in need of low cost butaccurately controllable electric power driving mechanisms.

Conventional wire printing apparatus, printing telegraph apparatus, andvarious forms of typewritting apparatus have used electric motor drivenpower rolls and linkages of expensive construction and criticaldimensions "ice for this purpose. Examples of this prior art are to befound in the following US. patents:

2,851,141, September 1958, Kistner, 197-1; 2,954,108, September 1960,Lenney, 192-81; 3,354,995, November 1967, Morris, 192-35; 3,386,650,June 1968, Hildebrandt et al., 234-123; 3,404,616, October 1968, Koeber,-45.

According to the invention, the objects indirectly related hereinbeforeand those which will appear hereinafter are attained in the mechanicalpower transmission system having a motor driven power roll, an operatinglever, a flexible band having one end attached to the operating leverand loosely arranged about the periphery of the power roll, a pressureroller carried by an arm arranged to move the pressure roller toward thepower roll for frictional engagement of the flexible band against themoving power roll thereby exerting a force on the operating lever tomove it about the pivot point. The device to be shifted is coupled byconventional means to a point on the operating lever moving in thedesired direction for the desired distance. The means for moving thepressure roller arm is coupled thereto by a disengageable latch normallyengaged in readiness for operation. The latch is arranged to bedisengaged by the operating lever as it is rotated by the power roll andflexible band at the point where the operating lever has reached thedesired displacement for shifting the device to be actuated. Anelectrically energized magnet, a manually operated key, or the like, isarranged to move the armature latched to the pressure roller arm. Thus,uniform travel of the device to be shifted obtains from applied forcewhich is not necessarily uniform as to duration applied or amplitude offorce or distance. traveled by the armature.

In order that the advantages of the invention may be readily attained inpractice, a description of the preferred embodiment of the invention isgiven hereinafter, by way of example only, with reference to theaccompanying drawing, forming a part of the specification and in which:

FIG. 1 is an isometric view of a power roll and actuator assemblyaccording to the invention;

FIG. 2 illustrates printing apparatus embodying the invention;

FIG. 3 is a schematic diagram of the mechanical power transmissionsystem according to the invention; and

FIG. 4 is a detailed drawing of one embodiment according to theinvention.

An assembly of a plurality of mechanical power transmitting levers andan electric motor driven power roll is shown in FIG. 1. A rigidframework 210 supports an electric motor 212 and a cylindrical steelpower roll 214 having a smooth peripheral surface made by an inexpensivemachine process. The shaft of the motor 212 and the power roll 214 aredirectly coupled; there are a large number of electric motorcommercially available which are suitable for the purpose. A number (13as shown of thin flexible bands 216 are loosely arranged about theperiphery of the power roll 214 with one end of each connected to anindividual operating lever 218, the uppermost portion only of which isseen here. A like number of device actuating levers 220, 229, 22Y, 22Z,and 230 are arranged in the frame 210 to pivot about the lower endsthrough very short uniform arcs with uniform forces toward and away fromthe longitudinal axis of the power roll 214. This movement is broughtabout in this embodiment by means of individual lever coupling links232. Individual to each band 216, is a pressure roller 234 arranged atthe end of a pressure roller arm 236 (just visible in this showing) anda pressure roller arm electromagnet 238 all arranged in the framework210. These components will be shown and described in greater detailhereinafter.

FIG. 2 shows an assembly closely similar to the one above describedinserted into printing apparatus of the type shown and described in theco-pending US. patent application, Ser. No. 829,653 for shifting aplurality of actuator plates of which only a spacing actuator plate 58and four character segment selecting plates 60-63 are shown in theinterests of clarity. The spacing plate actuating lever 230 extendsthrough apertures in the plates of such dimensions that the spacingselector Plate 58 only is moved forward by movement of the spacing plateactuator 230, either in response to electric energy applied to thepressure roller arm energized electromagnet 238, or the manipulation ofthe escapement release and carrier return lever 134 bearing on the upperend of the actuating lever 230. The spacing selector plate 58 is alsomoved each time the space bar 100, or any of the keys 70 are depressed,either to space manually or to space automatically after the selectionof a character segment. Others of the levers 22022Z will each actuateone character segment selecting plate and the spacing plate 58- Thereare instances in which all thirteen device actuating levers and allplates are moved and there are other instances when one out of eleven ofthe character segment selected plate device actuating levers are movedwhich also carries the spacing plate 58 forward at the same time. Inthis view, the operating lever 218 is seen to be in the configuration ofa hanger encircling the power roll 214 and the flexible band 216 on oneside rendering a very compact overall structure, The operating hangerlever 218 rotates about a fixed pivot 240 in the clockwise directionwhen the pressure roller 234 presses the flexible band 216 against theclockwise rotating power roll 214. In this illustration, the pressureroller arm 236 is made of resilient member welded to the armature 244 ofan electromagnet 238 in the configuration of an inexpensive relay. Inthis arrangement, the flexible band 216 is permitted to slip at the endof the strke of the device actuating lever 230 due to the resilience ofthe springy pressure roller arm 236. This springy arm release issatisfactory for many applications, however, a completely releasablelatch mechanism will be described hereinafter.

FIG. 3 is a schematic diagram illustrating the essentials of themechanical power transmission system according to the invention. Theoperating lever 218 pivots counterclockwise about the pivot point 240'by tension of the flexible band 216' exerted at the moving pivot point242. This movement is in response to the energizing of an electromagnet238 attracting an armature 244 rotatable clockwise about a pivot point246. A manual push button 248 might alternately be used to rotate thearmature 244. The rotation of the armature member 244' rotates thepressure roller arm 236 through the intermediary of a latch mechanismshown here as a first element 251 depending from the pressure roller arm236 at a moving pivot 254 and a second element 252 having one endconnected to the first element 251 at a moving pivot 256 and at theother end to a point on the operating lever 218 at a moving pivot 258.In operation, a shoulder portion 260 of the armature 244' urges thefirst element 251 upward to bring the pressure roller 234 intoengagement with the flexible band 216 and the power roll 214'. Thisaction rotates the operating lever 218 counterclockwise for movingdevices at either or both moving pivots 262 and 264 as desired. When theoperating lever 218' reaches the end of the predetermined rotationthereof, the first element 251 is urged off the shoulder 260 by thesecond element 252 so that continued energization of the magnet 238' (orcontinued pressure on the push button 248) will have no further controlof the operating lever 218 and the device connected to it.

FIG. 4 illustrates a preferred embodiment of the mechanical powertransmission system according to the invention. The driven power roll214" continuously r0- tates in the clockwise direction. A flexible bandof suitable material such as gasket paper material more commonly knownby the registered trademark Vellumoid or as polyethylene glycolterphthalate, more commonly known by the registered trademark Mylar isarranged loosely between the power roll 214" and the pressure roller234". The end of the flexible band 216" is connected to the operatinghanger lever 218" at the moving pivot point 242. When the pressureroller 234 engages the fiexible band 216" with the power roll 214", thehanger lever 218" rotates about the fixed pivot 240". A connecting rod232" is arranged in an extension portion 260" of the hanger 218 forsubstantially linear translation to the right. This draws a deviceactuating lever 220" through a short clockwise are about the fixed pivot262". The armature 244" rotates counterclockwise about a fixed pivot246". In this embodiment, the pressure roller arm 236 also rotates aboutthe fixed pivot 246". A moving pivot 254" is located on the pressureroller arm 236 remote from the pressure roller 234". Also rotatableabout the moving pivot 254" is a latch member having two portions 251"and 252". The first part 251" engages a pawl 260" portion of thearmature 244". When the armature 244" is attracted counterclockwise bythe electromagnet 238", portions 260 and 251" coact to rotate thepressure roller arm 236" counterclockwise urging the pressure roller234" into pressure translating relationship with the flexible band 216"and the power roll 214". When the operating hanger lever 218" hasrotated the predetermined distance, a disengaging pin 258 strikes theportion 252" of the latching arrangement causing it to rotatecounterclockwise and disengaging the pawl member 251" from the pawlmember 260 on the armature 244 thereby releasing the pressure roller arm236 and the pressure roller 234" from active relationship with theflexible band 216" and the power roll 214". With this arrangement,extension 260" exerts force over a uniform distance on the deviceactuating lever 220" despite any nonuniform amplitude or duration of theelectric pulse applied to the electromagnet 238".

While the invention has been shown and described particularly withreference to a preferred embodiment thereof, and various alternativestructures have been suggested, it should be clearly understood thatthose skilled in the art may effect further changes without departingfrom the spirit and scope of the invention.

The invention claimed is:

1. A mechanical power transmission system, comprising:

a continuously rotating drum,

2. flexible band arranged loosely about said drum with one end coupledto an end of a lever pivoted at a point beyond said flexible band,

a device to be powered coupled to the other end of said lever, and

a pressure roller arranged for pressing said free end of said flexibleband onto said rotating drum, thereby to actuate said lever and powersaid device.

2. A mechanical power transmission system as defined in claim 1 andincorporating an armature coupled to said pressure roller by a pawl andlatch arrangement for releasably engaging the two,

an electromagnet for attracting said armature, and

a pin arranged on said lever to engage said pawl and disengage saidarmature when said lever has traveled through the useful range.

3. A mechanical power transmission system, comprising:

a continuously rotating drum,

a flexible band arranged loosely about said drum with one end coupled toan end of a lever pivoted at a point beyond said flexible band andhaving the configuration of a hanger arranged about said rotating drumfor actuation by said band in a direction substantially tangentially ofsaid drum,

the pivot of said lever, the point of attachment of said one end of saidband to said lever and the longitudinal axis of said rotating drum beingsubstantially co-linear,

a device to be powered coupled to the other end of said lever, and

a mechanism for pressing said flexible band onto said rotating drum,

thereby to actuate said lever and power said device.

4. A ganged mechanical power transmission system comprising,

a continuously rotating elongated drum,

a plurality of flexible bands arranged loosely about said drum andside-by-side,

a plurality of hangers arranged about said drum and overlying saidbands,

said hangers being pivoted at points beyond said bands and on a lineparallel to the longitudinal axis of said drum,

said bands having one end of each attached to the overlying hangers atpoints on a line parallel to said axis and the first said line,

power takeoif links pivoted on said hangers above said hanger pivotpoints,

a plurality of elongated arms having pivots arranged in a line parallelto said axis and arranged on the side of said drum opposite saidhangers,

References Cited UNITED STATES PATENTS 2,742,131 4/1956 Petit 197 172,848,090 8/ 1958 Sharpe et al 197--19 2,851,141 9/ 1958 Kistner.

2,954,108 9/1960 Lenney.

3,354,995 11/ 1967 Morris.

3,404,616 10/ 1968 Koeber, Jr.

WILLIAM F. ODEA, Primary Examiner WESLEY S. RATLIFF, 111., AssistantExaminer Us. 01. X.R, 197-17

